Electron-discharge apparatus



Patented June 8, 1926. I

UNITED STATES 1,588,231 PATEN T OFFICE.

ALBERT W. HULL, 0F SGHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF .YORK.

' ELECTRON-DISCHARGE APPARATUS.

Application filed March 6, 1923.

My present invention relates to electron discharge apparatus of the magnetron type as described in a paper which was published in the Journal of the American Institute of gillectrical Engineers, September 1921, page In the operation of such devices for certain purposes it is customary to provide rent.

a polarizing magnetic field in order that the normal current flowing through the device may be adjusted to a value at which smallchanges in the magnetizing field will produce large changes in the value of the cur- If the source of potential employed for producing a flow of current through the device is a variable source the value of field strength at which the current will be reduced to substantiall zero varies With the square root of the v0 tage and the strength of the magnetizing field required for maintaining a desired value of current will vary accordingly. v

The object of my invention is to provide a means for. automatically varying the strength of the polarizing magnetic field to compensate for variations in the value of the potential applied between the electrodes. v M invention may conveniently be carried. out y producing the polarizing magnetic field b means of the same. source of potential w ich produces-a flow of current be tween the electrodes. If a resistance is included in the circuit, whereby the polarizing field is produced, having the characteristic that the current flow therethrough is proportional to the square root of the .voltage at its terminals and the value of this resistorganization and method of operation will best be understood by reference to the following description taken in connection with the accompanying drawing in which I have indicated diagrammatically one circuit connection whereby my invention may be carried into effect.

. tacle 1.

Serial No. 623,268. 1

I have indicated in the drawing an electron discharge device of the magnetron type comprising a tubular receptacle 1 enclosing operating value will be of such strength that the normal Value of current flowmg through the device will fall on a portion of the characteristic curve where small changes in the value of the magnetic field will produce large changes in current.

r The circuit for supplying heating current to the cathode also includes resistance 6 have. ingthe characteristic that the current flow therethrough varies in proportion to the square root of the voltage at their terminals. These resistances may be gas-filled tungsten lamps or other devices having the desired characteristic. The value of these resist ances should be large in proportion to the other resistance of the clrcuit.

The device which I have described may be employed as an amplifier by causing the currents to be amplified to'fiow through a magnetizing coil 7 surrounding the recep- Amplified currents may then be supplied directly to indicating devices in the circuit between the electrodes or by means of a transformer 8, the primary of which is included in the circuit between the electrodes, to other devices for utilizing the amplified currents or producing further amplification thereof. While I have shown and described the preferred embodiment of my invention it will be apparent that my invention is by no means limited to the recise embodiment indicated as many modi cations in the form' 1. The combination with an electron discharge device having an electron emitting cathode and a cooperating anode, of a. source no r the current therethrough is proportional to the square root of the voltage at its terminals.

2. The combination with' an electron discharge device having an' electron emitting cathode and a co-operating anode of a source of potential for producing a flow of current between said electrodes, means vfor producing from said source of potentiala magnetizing field between said electrodes and means for causing said magnetizing field to vary in strength in such a manner as to compensate for variations in the potential applied between said electrodes and maintain a desired value ofcurrent flow between said electrodes.

. 3. The combination with an electron discharge device having an electron emitting cathode and a co-operating anode of a circuit between said electrodes, a second circuit for producing a magnetizing field in the space between said electrodes, a common source of potential for supplying current to both circuits, and means in said second circuit for causing said magnetizing field to vary in strength in such a manner as to compensate for variations in the potential of said source and maintain a desired value of current flow between 'said electrodes.

4. The combination with an electron discharge device having an electron emitting cathode and a cooperating anode of a circuit .between said electrodes, a second circuit for producing a magnetizing field in the space between said electrodes, a common source of potential for supplying current to both circu1ts and a resistance in said second circuit having the characteristic that the current flow therethrough is proportional to the square root of the voltage at its terminals.

5. The combination with an electron discharge device having an electron emitting cathode and a cooperating anode of a circuit which includes means for producing a mag-' netizmg field between said electrodes and a resistance in said circuit having the characteristic that the current flow therethrough is proportional to the square root of the voltage at its terminals.

6. The combinatlon with an electron dis charge device having an electron emitting current to both circuits and a resistance in said second circuit having the characteristic that the current flow therethrough is proportional to the square root of the voltage at its terminals.

7. The combination with anelectron discharge device having an electron emitting cathode and acooperating anode of a circuit between said electrodes, a second circuit for supplying heating current to said cathode andfor producing a magnetic field in the space between said electrodes, a common source of-potential for supplying current to. both circuits and a resistance in said secondcircuit having the characteristic that the current flow therethrough .is proportional to the square root of. the voltage at its terminals.

8. The combination with an electrondischarge device having an electron emitting cathode and a cooperating anode of a circuit "between said electrodes, a second circuit for producing a magnetizing field in the space between said electrodes, a common source of potential for supplying current to both circuits and a gas filled tungsten lamp in said second circuit.

9. The combination with an electron discharge device having an electron emitting I cathode and a cooperating anode of a cir cuit between said electrodes, a second circuit a for supplying heating current to said cathode and for producing amagnetic field in the space between said electrodes, a common source of potential for supplying current to both circuits and a gas filled tungsten lamp in said second circuit.

10. The combination with an electron discharge device having an electron emitting cathode and a cooperating anode of a circuit between said electrodes, a second circuit forsupplying heating current to said cathode,

a common source of potential for supplying current to both circuits and a gas filled tungsten lamp in said second circuit.

"11. The combination with an electron discharge device having an electron emitting cathodeand a cooperating anode of a circuit which includes means for producing a magnetizing field between said electrodes and a gas filled tungsten lamp in said second circuit.

12. The method of operating an electron discharge device having an electron emitting cathode and a cooperating anode from a 

